From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jeff Garzik <jeff@garzik.org>
Subject: Re: Implementing NVMHCI...
Date: Sat, 11 Apr 2009 16:21:26 -0400
Message-ID: <49E0FBC6.3050600@garzik.org>
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To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>, Linux IDE mailing list <linux-ide@vger.kernel.org>, LKML <linux-kernel@vger.kernel.org>, Jens Axboe <jens.axboe@oracle.com>, Arjan van de Ven <arjan@infradead.org>

Linus Torvalds wrote:
> 
> On Sat, 11 Apr 2009, Alan Cox wrote:
>>> 	  The spec describes the sector size as
>>> 	  "512, 1k, 2k, 4k, 8k, etc."   It will be interesting to reach
>>> 	  "etc" territory.
>> Over 4K will be fun.
> 
> And by "fun", you mean "irrelevant".
> 
> If anybody does that, they'll simply not work. And it's not worth it even 
> trying to handle it.

FSVO trying to handle...

At the driver level, it would be easy to clamp sector size to 4k, and 
point the scatterlist to a zero-filled region for the >4k portion of 
each sector.  Inefficient, sure, but it is low-cost to the driver and 
gives the user something other than a brick.

	if (too_large_sector_size)
		nvmhci_fill_sg_clamped_interleave()
	else
		nvmhci_fill_sg()

Regards,

	Jeff